Redox-Controlled Polymerization and Copolymerization

Lewis acids in situ modulate pyridazine-imine Ni catalysed ethylene (co)polymerisation

The Lewis acid-base interaction between B(iii) Lewis acids and the pyridazine moiety reduced the electron density from the Ni center and in situ modulated the pyridazine-imine nickel catalyzed ethylene (co)polymerisation.

A continuing legend: the Brookhart-type α-diimine nickel and palladium catalysts

Here we will summarize some of the recent advances in α-diimine ligand developments, as well as some new and challenging monomers that this class of catalysts can address through these ligand improvements.

Synthesis and characterization of aminopyridine iron(ii) chloride catalysts for isoprene polymerization: sterically controlled monomer enchainment

Aminopyridine iron(ii) chloride complexes coordinating a type of flexible ligand are reported as precursors for controlled polymerization of isoprenes.

Investigation of a zirconium compound for redox switchable ring opening polymerization

Redox switchable catalysis with a ferrocene Schiff base zirconium complex allowed the synthesis of diblock and triblock copolymers.

Redox-switchable atom transfer radical polymerization

A redox-switchable ATRP was developed in which the copper catalyst, and hence the polymerization, was switched on/off using redox agents.

Accelerating ethylene polymerization using secondary metal ions in tetrahydrofuran

A variety of metal cations are capable of enhancing the ethylene polymerization rates of nickel phosphine phosphonate-polyethylene glycol catalysts.

Redox- and light-switchable N-heterocyclic carbenes: a “soup-to-nuts” course on contemporary structure–activity relationships

This Feature Article offers in-depth, design-to-application discussions of redox-switchable N-heterocyclic carbenes that have been field tested.

Improving the flame retardancy of polyethylenes through the palladium-catalyzed incorporation of polar comonomers

The flame retardancy of polyethylenes can be efficiently improved through the palladium catalyzed copolymerization of ethylene with polar comonomers.

Coordination–insertion polymerization of polar allylbenzene monomers

Utilization of polar allylbenzene allows for a much enhanced activity (9–6300 times) of polar allyl monomers in the coordination–insertion copolymerization.

One-Step Access to Sequence-Controlled Block Copolymers by Self-Switchable Organocatalytic Multicomponent Polymerization

A one-step procedure for the self-switchable block copolymerization of monomer mixtures of epoxides, cyclic anhydrides, and lactide (LA) was developed by using simple organocatalysts without an external stimulus. This multicomponent polymerization bridges two catalytic cycles involving ring-opening alternating copolymerization of epoxides with anhydrides and ring-opening polymerization (ROP) of LA, in which the presence/absence of anhydrides in mixed feedstocks switched the ROP of LA off/on. The self-switchable terpolymerization showed distinct noncoordinating and living nature, as well as perfect chemoselectivity. Different combinations of epoxides, anhydrides, and initiators enabled the generation of a variety of new block polyester polyols.

Efficient ethylene copolymerization with polar monomers using palladium anilinonaphthoquinone catalysts

Copolymerizations of ethylene with methyl acrylate (MA) and 5-norbornen-2-yl acetate (NB_AC) were explored using anilinonaphthoquinone-ligated palladium catalysts.

Mechanistic details of ethylene polymerization reaction using methallyl nickel(ii) catalysts

We present a mechanistic study of the ligand functionalization of bulky boron co-activators on neutral methallyl Ni(ii) catalysts for polyethylene production. This provides a blueprint for the development and design of catalysts with a high degree of tunability in a more efficient way.

Synthesis of poly(α-olefins) containing rare short-chain branches by dinuclear Ni-based catalysts

Chain walking mechanism with regard to dinuclear Ni-based catalyst stereoisomers in the polymerization of α-olefins: the effects of bridge, backbone and ortho-substituents.